Expansion Joint in Concrete

 Expansion Joint in Concrete

      Structures in which marked changes in plain dimension take place abruptly shall be provided with expansion on joints at the section where such change occur.

 Expansion joints shall be so provided that the necessary movement occur with minimum resistance at  the joint . the structures adjacent to the joint should preferably by supported on separated on separate column and walls but not necessarily on separate foundations . Reinforcement shall not extend across an expansion joint break between the sections shall be complete.

why expansion joint required 

The details as to the length of a structure where expansion joints have to be provided can be determined after taking into consideration various factors such as temperature exposure to weather the time and season of the laying of the concrete etc . normally structures exceeding 45m in length are designed with one ore more expansion joints . however in view of the large number factors involved in deciding the location spacing and nature of expansion joints, the provision of expansion joint in reinforced cement concrete structures should be left to the discretion of the designer . IS 3414 grieves the design consideration which need examined provide for.

Expansion joint Gap

  1. minimum 25mm 
  2. maximum 50mm
Used 
building and road ,hardstanding ,parking shad ,tunnel, bridge .etc .

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